Report urges protection of Candlewood Lake's watershed

When it rains around Candlewood Lake, the runoff carries a little bit of the world with it into the lake -- road salt, automobile grease and oil, lawn fertilizer, sediment, bacteria.

But when the lake's weeds get a nice fertilizer meal, when the lake's water gets a little less clear, people living around the lake -- and contributing to that pollution -- get upset.

A new report on the lake's water quality by the King's Mark Environmental Review Team makes the case that the lake is in danger from all this runoff and that the towns around the lake need to address the problem.

That shift toward eutrophication -- the process in which lakes receive a detrimental amount of nutrient in their run-off, nutrient that then feeds plant growth -- slowed in the 1970s and 1980s, Marsicano said, as federal and state governments began controlling the worst pollution.

But the decline is continuing -- just at a slower rate.

"It's inevitable unless we do the things that offset those changes,'' Marsicano said.

In 2008, the authority and the town of New Fairfield commissioned Kings Mark to write the report, in part because people in town questioned whether a proposed change in the town's zoning code to create a waterfront residential zone was worth the trouble. The King's Mark study was an attempt to answer those questions.

"It's pretty clear the train has left the station,'' she said of the lake's water quality problems.

The report states in its opening paragraphs that "the lake is under stress from high nutrient levels, jeopardizing many of its public uses and its value to surrounding communities.''

And while stormwater run-off -- the water that storm sewers carry into the lake is an important contributor to that pollution, the report states that "you cannot look at it in isolation, as there are many other environmental factors that contribute to water quality problems.''

The lake sites in a 25,000 acre watershed -- which, given Candlewood Lake's 5,420 acres of surface, is not particularly big, Marsicano said.

That means there are more paved, impervious surfaces and less undeveloped, vegetated land that can absorb run off rather than just spilling it into the lake.

Marsicano said a plethora of impervious surfaces can create a sort of chute, collecting and speeding run-off along. When it hits open ground, it doesn't spread out and sink in, Marsicano said. It keeps traveling fast, eroding the soil and carrying more of that soil into the lake.

There are things towns can do to slow this process.

Marsicano said Brookfield and New Milford have passed zoning regulations that regulate impervious surfaces in hopes of guarding water quality.

And New Fairfield has dropped its plans for simply creating a waterfront residential district. Instead, it's looking at changes in its zoning code that, for the first time, would regulate the area of impervious surfaces, as well as sections on storm water protection and erosion control.

Marsicano said with Brookfield and New Milford already passing tighter zoning regulations to protect water quality, and New Fairfield considering such a move, the last two towns surrounding the lake -- Danbury and Sherman -- should also consider such a move.